How to use Jackson to deserialise an array of objects

Question

The Jackson data binding documentation indicates that Jackson supports deserialising "Arrays of all supported types" but I can't figure out the exact syntax for this.

For a single object I would do this:

//json input {     "id" : "junk",     "stuff" : "things" }  //Java MyClass instance = objectMapper.readValue(json, MyClass.class); 

Now for an array I want to do this:

//json input [{     "id" : "junk",     "stuff" : "things" }, {     "id" : "spam",     "stuff" : "eggs" }]  //Java List<MyClass> entries = ? 

Anyone know if there is a magic missing command? If not then what is the solution?

Answer 1

First create a mapper :

import com.fasterxml.jackson.databind.ObjectMapper;// in play 2.3 ObjectMapper mapper = new ObjectMapper(); 

As Array:

MyClass[] myObjects = mapper.readValue(json, MyClass[].class); 

As List:

List<MyClass> myObjects = mapper.readValue(jsonInput, new TypeReference<List<MyClass>>(){}); 

Another way to specify the List type:

List<MyClass> myObjects = mapper.readValue(jsonInput, mapper.getTypeFactory().constructCollectionType(List.class, MyClass.class)); 

Answer 2

From Eugene Tskhovrebov

List<MyClass> myObjects = Arrays.asList(mapper.readValue(json, MyClass[].class)) 

This solution seems to be the best for me.